Eager to prove their relevance among scholars leaving print behind, libraries have participated vocally in the last half-decade's conversation about digital research data. On the surface, libraries would seem to have much human and technological infrastructure ready-constructed to repurpose for data: digital library platforms and institutional repositories may appear fit for purpose. However, unless libraries understand the salient characteristics of research data, and how they do and do not fit with library processes and infrastructure, they run the risk of embarrassing missteps as they come to grips with the data challenge.